In such a prosthesis, the locking element is maintained in position on the ulnar component thanks to a screw introduced in a through housing in this element and tightened in a tapping provided on the ulnar component. It has proved in practice that the positioning of the locking element on the ulnar component is not always optimum when such a screw is tightened, which may lead to a skewed positioning of the screw with respect to the tapping, to such a point that the thread of the screw or the tapping may be distorted, thus preventing the locking element from being mounted. In addition, the afore-mentioned screw serves both to bring the locking element into correct position with respect to the ulnar component and to ensure blocking of these two elements with respect to each other. As a result, such an ulnar component must most often be fitted while the articulation of the elbow is in maximum flexion, which renders the surgeon's work more complex. It even happens that such fitting in maximum flexion is not possible, particularly in the case of marked obesity of the patient.
It is a more particular object of the invention to overcome these drawbacks by proposing an elbow prosthesis whose fit is facilitated, when it comprises a locking element as mentioned hereinabove.